Disclaimer: I don't know anything about Julia, except from reading a couple simple programs just now, and seeing that it uses syntax that looks somewhat like Algol.
I don't think there's any inherent contradiction between the two, depending on what you mean by "the power of homoiconicity" (1). Homoiconicity doesn't mean you need to use lists: you could make a language like C but with native structures to hold all of the syntax. It's just that "cons cell and symbol" happen to be a really simple set of tools from which you can build everything you need.
I suspect that languages that try to have both do it by sacrificing simplicity. They have syntax that looks like C, and then make it homoiconic by building essentially a DOM for all of that syntax. Perhaps the idea is that writing and reading "x = y + z" is deemed sufficiently common that they're OK with making metaprogramming more complex if they get to keep Algol syntax.
(1) By "depends on what you mean", I meant: is simplicity requisite for power? I would say "yes", but I can imagine there's someone who would say "no" and consider Algol-plus-DOM (is that what Julia is?) to be as powerful as simpler languages.